1. I think this mechanism is likely relevant in humans, and that the idea of a critical window of development is also very applicable to humans. The gestational period is crucial and thought to be associated with fetal epigenetic programming, and analogous behaviors that could influence this programming would include behaviors in the mother that decrease stress and promote mental and emotional well-being. I also think that the early newborn period up until 3-5 years of life is also a critical window. In the immediate newborn period, skin to skin contact at birth with both parents could represent an analogous behavior. During the later early childhood years, analogous behaviors could include speaking, reading, and singing to the child, showing affection, and behaviors that reduce stressors in the household.
2. To some extent, I think they are consistent, in that SES adversity in childhood could potentially influence epigenetic programming, albeit in an opposite manner than the health-promoting behaviors such as licking and grooming. We know that epigenetic mechanisms can work in opposing directions, so it is not unreasonable to believe that certain behaviors or exposures lead to “protective” epigenetic programming whereas some, like SES adversity, could lead to “detrimental” programming. However the two perspectives differ in that Gruenewald emphasizes the importance of cumulative effects of adversity over a lifespan, whereas Weaver emphasizes critical or sensitive periods in early development.
3. I think GxE interactions intuitively make sense, especially when considering that common genetic markers can be expressed differentially depending on the individual, and it is possible that environmental differences could explain part of this differential expression. However, while these interactions may play a small part in explaining health care disparities, I think there are other factors that play a much larger role. Specifically, I think structural factors including racism are not accounted for in the GxE model, and I believe these are much larger contributors to these disparities because they consider the individual’s larger social and political context, rather than simply his or her environmental context.